FrankenRupp build

#2
Cool. Are you going with a flathead in this one? A OHV may not fit. Is it a 2 speed or is that a brake drum. If it's a 2 speed, you'll probably like that. I have a couple of sears and a Boonie with the 2 speed. You should be able to make a nice ride out of that one.:thumbsup:
 
#3



I decided to get started on this old Rupp today and went ahead and stripped and primed the frame and fork.

Anyone have any suggestions for brakes? I don't have the factory Rupp wheels and am trying to figure out something that won't involve welding. Any suggestions? Maybe someone has some old Rupp wheels with the brakes that would work?

Also, the components on the jackshaft are toast. I would like to just scrap the 2-speed setup and just use a two sprockets jackshaft. Can I just drill and pin a couple of sprockets to the existing shaft? Would an Azusa shaft drop-in and be easier to deal with? I am welcoming any suggestions.

Yes, Kenny I know where I can get a seat!:smile:

I found these pics on the pitpro.com site and I guess it is basically what I am after. Notice the jackshaft appears to have a sprocket mounted on the outside of the frame.




 
#4
Jim-

I think you put one it before I could post. Do you think I should just keep the 2-speed? I see some of the complete jackshafts on ebay that appear to be like the Rupp, but I can't be certain.
 
#5
You could get a keyed jackshaft and cut it to length. If you have a bearing supply store nearby, they'll have shafting bearings and sprockets on hand. I always go to A&w bearing here. Very reasonable prices.
 
#7
ruppparts.com sells a 2 speed that is supposed to have an improved shifting point. The ones BMI sells on ebay should work. The length may not be right, but that's no biggie. If your bearing holes are 1 3/8, you should be ok. I think BMI sells the entire setup for around $100, double sprocket engine clutch included.
 
#9
i have the 2 speed clutch from bmi karts on my franken rupp! good name for it. I was told the 2 speed clutches from bmi have a smoother shifting point, and the rupp ones shift hard into 2nd. And by the way the bmi comet 2 spped set up went right into my frame and didnt have to adjust anything but the sprocket to the rear wheel.
 
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#10
Preston, I saw some seats on ebay I think.
LOL...I bet! I will be grabbing one of those sometime during this project.

i have the 2 speed clutch from bmi karts on my franken rupp! good name for it. I was told the 2 speed clutches from bmi have a smoother shifting point, and the rupp ones shift hard into 2nd. And by the way the bmi comet 2 spped set up went right into my frame and didnt have to adjust anything but the sprocket to the rear wheel.
Well, I guess that takes care of the jackshaft. I'm getting that one from BMI. I like your FrankenRupp by the way.

Now I'm going to need some brakes. If the easiest way means I have to replace the wheels, then so be it.
 

kbs8ball

Active Member
#11
the easiest brake system???? get some good boots!!! I dont think ive had brakes on any of my bikes for there maiden voyage. just gotta be careful.
 
#12
the easiest brake system???? get some good boots!!! I dont think ive had brakes on any of my bikes for there maiden voyage. just gotta be careful.
Yeah right, the original "foot brake" ala Flintstones.

I did a little research on brakes and it appears the expanding brakes would work.
 
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